Mechanoreceptors observed in a ligamentous structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament

[Research progress of anterior cruciate ligament reconstruction with over-the-top technique]

OBJECTIVE

To review the research progress regarding the over-the-top technique for anterior cruciate ligament (ACL) reconstruction.

METHODS

The relevant literature on ACL reconstruction using the over-the-top technique was analyzed for its evolution, clinical application, advantages, and limitations.

RESULTS

Over-the-top technique for ACL reconstruction is a combined intra- and extra-articular technique. Because it avoids drilling the femoral tunnel, its advantages are mainly highlighted in the protection of the femur. Therefore, it is widely used in children and adolescents with epiphyseal occlusion and in patients with revision reconstruction. In addition, significant improvements in postoperative joint stability, functional scores, and return to exercise rates are found in long-term follow-up studies of patients with primary ACL reconstruction and combined anterolateral tenodesis. However, the technique also has some limitations, such as poor stability of knee flexion after operation, high requirement for graft length, and easy impact of graft in the intercondylar fossa.

CONCLUSION

The current research results show the effectiveness and safety of the over-the-top technique for primary and revision ACL reconstruction, with the advantages of wide application, simple operation, and quick recovery; however, more researches are needed to further optimize the selection of grafts and femoral condyle management problems, and to clarify the long-term effectiveness.

Can MRI knee joint measurements predict the population at risk of ACL injury?

BACKGROUND

Anterior cruciate ligament (ACL) injuries have been increasing significantly over time. The relationship between the ACL injury and the knee joint structures is poorly understood. The purpose of this study is to examine whether the measurements of different structures in the knee joint are linked with ACL injury in affected patients.

METHODS

This retrospective case-control study included patients who suffered from ACL tears and underwent magnetic resonance imaging (MRI). A control group of patients with no knee pathologies on MRI was included. Fourteen knee variables, including lateral meniscus (LM) posterior horn height, length, depth, and volume; medial meniscus (MM) posterior horn height, length, depth, and volume; lateral and medial (MFC) femoral condyle sphere diameter; lateral and medial tibial plateau length; and patella tendon horizontal and vertical diameter, were collected. A multivariate logistic regression including LM posterior horn depth, MM posterior horn length, MM volume, MFC sphere diameter, and patella tendon horizontal diameter and receiver operating characteristic curve, was used to compare the two groups.

RESULTS

A total of 85 patients were included in our study; 54 suffered from ACL injuries and 31 as a control group with normal knee MRI. Logistic regression revealed that increased LM posterior horn depth (OR = 1.27; 95% CI = 1.03-1.56; p = 0.028), decreased MM posterior horn length (OR = 0.71; 95% CI = 0.55-0.93; p = 0.013), and MFC sphere diameter (OR = 1.20; 95% CI = 1.01-1.43; p = 0.035) were independent risk factors for ACL rupture. The MFC sphere diameter yielded the highest area under the curve: 0.747 (95% CI, 0.632-0.862). No difference was found in the other measurements between the two groups.

CONCLUSIONS

Concerning the difference in anatomical variations, the lateral meniscus posterior horn depth and medial femoral condyle sphere diameter were higher, while medial meniscus posterior horn length was lower in patients with an ACL injury. These structural knee measurements could have a possible increase in the likelihood of sustaining an ACL injury and can be used by clinicians to predict ACL injury.